A greatest hits album, sometimes called a "best of" album or a catalog album, is a compilation of songs by a particular artist or band. Most often the track list contains previously released recordings with a high degree of notability. However to increase the appeal, especially to people who already own the original release, it is common to include remixes and/or alternate takes of popular songs; even new material (previously unreleased). At times a greatest hits compilation is the original release for songs that have themselves been released as a single and charted successfully.

In British pop music, when a band releases a greatest hits album, in most cases after three or four studio albums, it is usually taken as a sign that the band are about to split up.[citation needed] Examples include greatest hits albums by Atomic Kitten, Steps, S Club 7, Blue, JLS, Five and Take That, although the latter band would reform nine years later. Recent exceptions to this "rule" include Westlife, Girls Aloud, McFly, and Sugababes, who have released new material after their greatest hits collections. In other cases, Greatest Hits will be released to capitalise on the renewed popularity of a newly reformed band. An example of this is Take That's Never Forget and Spice Girls' Greatest Hits.

Some bands refuse to release a greatest hits album, notably AC/DC, Tool and Metallica, (AC/DC, however, has released two compilation albums in the past: Who Made Who and Iron Man 2, which are both movie soundtracks). Manic Street Preachers initially refused to do a greatest hits, but in the end Forever Delayed was released. A later release, National Treasures - The Complete Singles, was selected and endorsed by the band. Radiohead also refused to do such a compilation, but upon their departure from Parlophone Records, Radiohead: The Best Of was released without their cooperation.[2] This was initially to be the case with Oasis, but upon realization that the release was inevitable, the band took direct involvement, selecting the tracklisting, track order, and the artwork. The country music star Garth Brooks long opposed the release of a greatest hits collection, but agreed to it in 1994[3] but only for a limited time[4] (his release, The Hits was quickly deleted, but not until selling well over ten million copies). Joni Mitchell also resisted releasing a greatest hits album for many years, reportedly fearing that the availability of a greatest hits compilation would lead her record label to take her actual studio albums out of print, but she agreed to release Hits in 1996 along with a second album titled Misses, which compiled non-hit songs that Mitchell personally selected as being representative of her work.

One of the most notorious examples of a greatest hits compilation released against the artists' intentions is The Rolling Stones compilation Hot Rocks 1964–1971. After their manager tricked the band into signing over the copyrights to their 1963-1970 song catalog, the band quickly changed management and record labels. However, they could not prevent the release of Hot Rocks and its successor, More Hot Rocks (Big Hits & Fazed Cookies). A testament to the selling power of greatest hits albums, Hot Rocks remains the best selling album of the Rolling Stones' career. Note that Mick Jagger and Keith Richards continue to collect significant songwriting royalties from the Hot Rocks sales, but not the ownership royalties.

Greatest hits collections can also boost a falling music career. The Beautiful South's first greatest hits album, Carry On up the Charts, was originally strongly opposed by the band. However, upon release it became one of the fastest selling albums in chart history.[5]

Often, a greatest hits VHS or DVD collection can be released, which features the music videos to the hits. These are often released concurrently with a Greatest Hits album (a more recent example being the Oasis release Time Flies... 1994–2009). Although sometimes, a Greatest Hits VHS or DVD can be released as a solo release without a companion album (a good example being the Guns N' Roses VHS/DVD Welcome to the Videos, released in 1998. Guns N' Roses would eventually release a greatest hits album in 2004). Another example of a video greatest hits without a companion audio album would be Positive Mental Octopus by the Red Hot Chili Peppers, released in 1990. However, in 1992, the band released a video called What Hits?!, which contained all the videos from Positive Mental Octopus and also had an accompanying album. Occasionally, a DVD release will feature music videos for singles that were not included on the Greatest Hits album. Whilst the Greatest Hits album might only contain a small number of singles, A DVD release will often contain all the band's music videos up until that point. Two examples of this are Blur's The Best Of DVD and Jamiroquai's High Times. to go with Radio stations are now emerging that only play Greatest Hits albums as their source material.[6]Queen have released Greatest Video Hits and Greatest Video Hits 2.

Another criticism has been including one or two new songs with a package of hits. This trend started in the early 1980s, and made it necessary for collectors to purchase the "greatest hits" album if they wished to have the complete catalog of an artist's songs, even if those collectors owned all the albums containing the pre-existing hits. By contract, another solution to acquire only the songs, via an online music store, may also be restricted to purchase of the album only, even online. The Paperboys released Tenure in 2002, which, out of its eighteen tracks, contains six new songs.

The quality of a greatest hits package released early in an artist's career depends upon the artist. Elvis Presley released Elvis' Golden Records in 1958, which only covered 1956–1958, although this album still sells today, remaining in print on Compact Disc, despite the many Presley hits collections issued since. The Bee Gees released Best of Bee Gees in 1969, only two years after their international debut, yet nine of the twelve tracks were hit singles in America. Sly and the Family Stone released their Greatest Hits album in 1970, after only three years. Ringo Starr's Blast from Your Past and John Lennon's Shaved Fish came out in 1975, after five-year solo careers (both had been in The Beatles). ZZ Top's Greatest Hits was released in 1978, as a contractual obligation with no new tracks, but since its CD release has been popular because of its use of the original mixes of songs (the CD releases of their parent albums have overdubs made in the 1980s). All of these compilations were well received and continue to garner critical kudos.[7][8][9][10]Bob Marley's Legend remains his best selling album despite many more posthumous hits since, and more thorough compilations being released later on.

In Japan, it is common for artists to have "greatest hits" compilations released early in their career. Many acts release a compilation after three albums, which commonly means after only three years of career in the music market. Ayumi Hamasaki, Mai Kuraki, Hikaru Utada, Glay and Greeeen are a few examples (the band McFly, from England, also released a greatest hits album after three albums and three active years). Many times, the decision of having a greatest hits released is due to the popularity of the artist at the moment, which results in bigger sales. It is also common for the Japanese artists to have many compilations throughout their careers.

A recent trend is for television shows to release compilation DVD's of their most well-regarded and highest-rated episodes to drive new viewers to watch a program. Two examples of this are the Family Guy's Freakin' Sweet Collection and South Park: The Hits. Several video game companies have game rereleases after they have sold a certain number; Sony's PlayStation has a "Greatest Hits" banner; Nintendo has the Player's Choice label; and Microsoft has the Xbox Platinum Hits label. The European title (and original North American title) for Guitar Hero Smash Hits was Guitar Hero: Greatest Hits. The Simpsons released Greatest Hits on VHS in 1998.

^Patterson, Jim (1995-02-17). "Garth Brooks knows how to take 'The Hits'". Associated Press. Retrieved 2009-07-29. I hate the idea of the greatest hits being out there," Brooks says. EMI won him over with a solution that made sense to his adman side. EMI agreed to sell "The Hits" for only four to six months, meaning that fans better pick it up by this summer or they're out of luck. (Archived by WebCite at http://www.webcitation.org/5idiLY7Rt)